Click here to purchase the entire book in PDF format. Red Noise (aka Brown Noise or Popcorn Noise) Red Noise is used when pink noise isn't low-end-heavy enough for you. For example, in cases where you want to use noise to simulate road noise in the interior of a car, then you want a lot of low-frequency information. You'll also see it used in oceanography. In the case of red noise, there is a 6.02 dB drop in power for every increase in frequency of 1 octave. (In other words, the power is proportional to $\frac{1}{f^{2}}$)